In order to provide a smooth and beautiful appearance, a casing of a display device is usually smooth and non-chamfered. However, in specific environment, such as eSports market, the display device needs to provide a hanging device for placing the user's headband receiver. There are two types of traditional hanging devices for the display device. One of them is to attach a hook to a lateral surface of the casing by glue. But, when the glue loses adhesion, the hook will fall off to casus. Accordingly, it provides unstable supporting strength. Another type is that the hook is fixed to the lateral surface of the casing by a screw. Although the screw may provide better bonding strength, the structure of the casing is easy to be damaged and the appearance of the display device is contrived.